Manufacture of artificial silk



June 28, 1938. A. J. EN'GEL I 2,122,092

- MANUFACTURE OF ARTIFICIAL SILK I Filed Dec. 6, 1955 2 Sheets-Shet 1 SKIMM June28,1938. 2,122,092

MANUFACTURE OF ARTIFICIAL SILK Filed Dec. 6, 1955 2 Sheets-Sheet 2 Qwucmkon Shame/x5 I employed are, first, the simple stroke displace-- traverse guide as taught by this invention show- Patented June 28, 1938 or Anemia s Antonie Jacobus Engel, Arnhem, Netherlands,

assignor to American Corporation, Erika,

N. 0., a corporation of Delaware Application December 6, 1935, Serial No. 53,254

In the Netherlands December 8, 1934 8 C a: 1 Ms This invention relates to traverse mechanism of the type generally used in the production of bobbins and more particularly to means for forming the tapered winding on the end of the bobbin spools.

When winding textile materials, particularly artificial silk, as is known, a traverse varying device is employed by means of which the material obtained from the spinning process is guided so as to be deposited on bobbin spools in a predetermined form. Traverse mechanisms have been employed heretofore which give the winding on the end of the spool a conical shape, but these have not proved to be satisfactory because of the difference in density between'the end edges of the winding and the main body portion thereof. Spools or bobbins formed in this manner cannot be washed, dyed, or dried evenly.

When winding bobbins with freshly spun rayon the traverse movements most generally used are almost always made up of one main movement combined with one or two auxiliary movements. The main movement being that obtained by allowing the roller of the thread guide arm to roll around the periphery of a cam of predetermined shape. The auxiliary movements ment and the regular stroke shortening movement that takes place during the spinning period, and secondly, the Pilgrim Step. These movements are distinguished one from the other by the ratio between the number of rot'ations'of the auxiliary movements and the rotations of the main movement. When using the stroke shortening movement as referred to above, then during the entire winding on period the auxiliary movement moves only once causing the amplitude of traverse to change from a maximum in starting the winding on period to a minimum on the completion of the winding on period. Then when the Pilgrim Step is employed the auxiliary movement may make twenty times as many rotations as the main movement thereby causing the guide to oscillate backward and forward in its path across the spool or bobbin a corresponding number of times. Using the stroke displacement movement the auxiliary movement may turn as much as one twentieth the speed of the main movement thereby causing the amplitude of traverse to decrease to a minimum and build up to a maximum during 20 cycles of the guide.

having a frusto-conical shape. However, the form of the spool or bobbin ends does not depend upon the number of rotations of the auxiliary movement but exclusively upon the speed pattern of the auxiliary movement.

Therefore, an object of this invention is the provision of mechanism whereby thread can be wound upon bobbins to form a package having end edges thick enough for proper washing, dyeing, or drying.

This invention also contemplates apparatus whereby a spool or package of thread is formed which will be free from noticeable ridges.

This invention further contemplates the pro-' vision of a mechanism whereby a number of the above described movements may be combined to give the desired type of winding.

Other objects, advantages and characteristic features of the invention will become apparent as the description of the disclosed embodiment progresses, reference being had to the annexed drawings in which:

Figs. 1, 2 and 3 are diagrammatic representations of fragmentarylongitudinal sections of cylindrical windings showing the different eiiects produced in forming the winding with different arrangement of traverse mechanism;

Fig. 4 is a diagrammatic illustration of the mechanism} Fig. '7 is a detail vertical longitudinal section along the line 'l-,-'l of Fig. 6 showing the gear train employed in driving the auxiliary cam;

Fig. 8 is a vertical section of a modification of the gear train shown in Fig. '1, showing the use of a different gear ratio; I

Fig. 9 is a vertical section of a second modification of the auxiliary cam driving mechanism.

Referringto the drawings, particularly Figs. 6 and "l, the mechanism is driven by a main drive shaft III that is connected to a suitable source of power not shown. A hub I l is fitted on the opposite end of shaft I0 and adapted to turn with the shaft to drive the main eccentric or cam I2.

Eccentric I2 is substantially heart-shaped in form and the periphery thereof serves as a track on which the roller \end of a bell crank, which serves as the thread guide arm, is adapted to move. member l3 which is adapted to move in a line which is at right angles. to the shaft. Provisions for such movement are made by slotting member l3 as shown at M and IE to receive the driving crank pin l6 and the hub II respectively. The crank pin 16 is secured to a crank arm I! which is made integral with hub H, by means of a bolt l8. Such'an arrangement is provided to permit the .main cam I2 to move along its center line i. e., its line of symmetry, with respect to the main drive shaft l0. Springs I 9 are connected to hub I I and the cam I2 and thereby normally tend to force the point of cam I 2 toward the main shaft In. This movement, however, is limited by roller 22 that is mounted upon the guide member l3 by means of bolt 2|. A second or auxiliary cam or eccentric member 22, the periphery of which forms the path for roller 20, governs the movement of the main cam with respect to the shaft. Thus it can be readily seen that although the main cam I2 is adapted to slide on the shaft along its center line, it is also caused to rotate by the shaft. Cam 22 is keyed to and adapted to be driven by bushing,23. Bushing 23 is driven by means of gears 24, 25, 26 and-21 from the main shaft l0. These gears obviously may be given any desired ratio to obtain varying relative speeds between cam 22 and cam I 2. As shown in Fig. 8 a gear ratio may be selected which will cause the cam 22 to be driven at a relatively higher speed than cam l2, while on the other hand should it be desirable to drive cam 22 at a somewhat lower speed than cam I2, an arrangement of gears'such as is shown in Fig. 9 may be employed. The gears 24-21 must have then e. g. 34, 34, 29 and 39 teeth respectively.

The form that the winding will take on the spool is directly dependent upon the speed pattern of cam 22. Therefore, the shape of ,cam 22 must be of such contours as will give the desired form to the winding. In operation if it is desired to employ the Pilgrim Step" movement in wind ling a thread on a spool or bobbin the cam 22 must, of'necessity, be driven at a higher speed than cam. I2. This will effect an oscillatory movement of the thread guide arm which will cause the thread to move forward and backward a number of times corresponding to'the ratio of the speeds of the respective cams during each traverse of the spool or bobbin. It is to be understood that cam 22-will have the desired contours to effect a proper shape of winding. The Pilgrim Step movement may be accomplished by utilizing a gear trainv such as that disclosed in Fig. 8, the gears 2t- 21 having for example I respectively 45, 23, and 23 teeth.

If it is desired to wind the bobbins by the stroke shortening movement, then, of necessity, cam 22 must be driven at a much slower speed than cam l2. A gear train such as shown in Fig. 7 may be employed to effect this movement, the number of teeth of gears 26-2'I being respectively 151, 150, 149 and 150. Driving cam 22 slower than cam i2 will cause'the thread guide arm to move through a path traversing the spool from maximum amplitude or the longest stroke to an amplitude which approaches zero as a limit or the minimum stroke in the first 180 movement of cam 22. As cam 22 completes one revolution or the second 180 the amplitude of traverse of the thread guide will increase to a maximum. Regardless of the number of revolutions made by the cam 22 relative to the cam l2 the shape of the winding on the spool will remain the same The eccentric I2 is secured to a guidev pending upon the form-of movement that is to be employed in forming the winding. First let us suppose that the bushing turns very slow as compared to the main cam, for example, no more than 180 per wind on. Then, the cam will move with respect to the driving shaft in such a way that during the winding on period the stroke of the cam decreases regularly. The eccentric bushing thus determines the speed at which the stroke will decrease and if it is assumed that the relative rotation of the eccentric bushing as compared to the cam is of a uniform speed, then it follows that the displacement of the cam during the beginning of the winding on period takes place very slowly. However, during the winding on period it will increase, then toward the middle of this period, the speed of displacement will reach a maximum. Thereafter the speed of displacement will decrease and toward the end of the winding on period will approach zero as a limit. Thus it can be seen that the speed pattern of displacement will assume the form of a sine curve. 'In this case the frustoconical ends of the spool package will appear as indicated in Fig. 1 by the heavy line.

Alterations in the relative speed of the cam and bushing will not change the theoretical form of the spool end. When the eccentric bushing is turned 360 instead of 180 relative to the cam during one winding on period the stroke is as indicated above throughout the first part of the period, but twice as fast. The package thus formed up to this point will only,have one-half the thickness of that discussed above. However, during the movement of the eccentric bushing through the remaining 180 of the winding on period the stroke will increase again and the movements will be exactly opposite to the ones in the first half. I The changes of the stroke are equal, but opposite, consequently the package is built up exactly as in the first instance. In either case the package retains the same form regardless of whether the eccentric bushing makes one revolution or many relative to the cam. So Fig. 1 illustrates ,also the form of the spool or package formed by the simple stroke displacement or Pilgrim Step traverse produced by the auxiliary movement derived from the eccentric bushing in the cam.

Due to the fact that the thread lags on making the return stroke relative to the thread guide, one does not get the theoretical form ofspool end. The lagging of the thread relative to the guide on returns will result in an extra turn of yarn being deposited on all points of the return and with a given number of returns these surplus turns will amount to a substantial quantity of yarn. It can readily be seen that whenever the change in the length of stroke is small there will be a greater number of reverses that will come together and the amount of yarn built up as a result of the lag will increase accordingly. In

posed for reducing the stroke is one which effe ts a constant speed displacement of a main cam along a line at right angles to the axis of rotation. A spool produced when utilizing this movement is of the form, theoretically, as illustrated by the fulllines in Fig. 2. The lagging, of the thread, however, will cause the shape of the spool to assume a form such as is indicated by dotted line in this same figure. Although the ridges are much smaller than those illustrated in Fig. l in dotted line,'they are, nevertheless, of substantial size and, of course, are objectionable. Other difficulties encountered in using such a movement are, that the winding on the end of the spool'is too thin and introduces difficulties when subjected to suction or pressure wash due to the fact that the permeability of the end of the winding is so much greater thanthat of the midsection.

A spool or package of thread formed by utilizing the mechanism and method set out herein may have a form such as is illustrated by Fig. 3 i. e. the sectional contour of the end of the winding can be of a form corresponding to a logarithmic curve. This form has the advantage, that it gives an even permeability in pressureor suctionwashing and that it is free of ridges. This is possible because the thread lags when it reverses and a crossing different from that in the cylindrical part results, thereby effecting a lesser degree of permeability per unit thickness of package, which provides the necessary equalizing factor. The varying of the thickness after a logarithmic curve'is obtained by making the speed of the'auxiliary motion for stroke reduction increase regularly from the beginning to the end of the wind on period. The constructions hereto known. can not give such a form, as they have not the characteristic of my invention, that the two traverse movements are combined in such a way that the auxiliary movement is employed only to move the main cam or eccentric member in its position relative to the shaft, while in each position this main cam alone determines the length of the stroke. So the form of the auxiliary cam can be chosen freely, as at any moment only one point of.it is working.

The shape of the extreme ends of the spool is only afiected by the change in shape of the auxiliary cam in the vicinity of the point which has the greatest radius, and that portion of the spool end defined by the extreme outer end of the spool and the cylindrical portion thereof is dependent for its shape on the shape of the auxiliary cam in the vicinity of its smallest radius. Therefore,

' it is obvious that regardless of the movement employed any desired shape of winding can be obtained by the selection of an auxiliary cam having the desired contours.

The position of the thread guide has been diagrammatically indicated in Figs. 4 and 5 for maximum strokes. Its position is definable in one extreme position by the dimension A of the main cam plus dimension "a of the auxiliary cam and in the other extreme position by 28" minus 11". Therefore, the total stroke is (A plus a.") minus (3 minus "113) and is equal to A minus 3 plus 2 a. Minimum stroke may be obtained by rotating the auxiliary cam 180 (see Figures 4 and.5). In this case the roller is then closer to the shaft and the stroke is "A" minus 13 plus 2 b.

The operation of the apparatus will be readily apparent from the foregoing description. During rotation of the drive shaft in, the main heartshaped cam l2 and the aumliar'y cam 22 will be eating form of guide member.

driven in the same direction at uniformly different speeds by reason of the gears 24, 25, 26 and 21 which transmit power from the shaft II), with which the main cam is operatively connected, to the bushing 23, to which latter the auxiliary cam is keyed. The main cam i2 is thus free'to move me line corresponding to its line of symmetry -that is, in a line which bisects the cam into two symmetrical parts-and is held by' line of symmetry .under'the influence of the auxiliary cam.

The main cam being heart-shaped, the shape of the auxiliary cam is preferably so selected that the main cam moves smoothly along its line of symmetry between its two extremes of travel with a speed of movement that increases with a decrease in the distance between the highest point of the main cam and its axis of rotation, and vice versa. Also the auxiliary cam is so formed that the cam throws of successive points of its periphery vary in accordance with a logarithmic curve.

In this way the thread guide carried by the traverse mechanism travels back and forth along the spool or bobbin with the speed of the auxiliary motion imparted by the auxiliary cam regularly increasing during the period of the shorteningof the stroke of the thread guide. 1 This results in a package having the general form indicated in Fig. 3 in which theend edges are substantially free from ridges and are of a suitable density for proper washing, dyeing and drying. While the invention in-its preferred form contemplates the employment of an auxiliary cam of the logarithmic character described above, it will be apparent that in its broadest aspect the invention is not limited to any particular shape of auxiliary cam, and that the shape of such cam may be suitably selected according to. the desired form of the package to be wound.

, Although for purpose of illustration and explanation this invention has been described in connection with a thread guide that is fastened to the end of a swinging lever of the bell crank type, the invention is equally applicable to the recipro- In fact, it would find application to substantially all forms of traverse mechanisms employed in the spinning art.

"Permeability" as used herein is defined as that quantity of water which will flow through one square centimeter of the surface of the package at a given pressure in a given interval of time, while "wind on or winding on" period, I as used herein, refers to a period in which the spool or package is completely wound.

I What I claim is:

1. In an apparatus for winding spools or bobbins, a traverse actuating mechanism comprising a main cam of symmetrical shape and adapted to control the thread mechanism, an auxiliary cam located adjacent the main cam and independently rotatable with respect thereto, means supporting the main cam for displacement along its line of symmetry, means extending between the main cam and auxiliary cam whereby relative rotation between the guide arm of the traverse cams causes displacement of the main cam along its line of symmetry and means for rotating the cams at relatively different speeds.

respect thereto, a roller supported by the auxiliary cam, means yieldingly retaining the roller in engagement with the periphery of the auxiliary cam whereby relative rotation between the cams causes displacement of the main cam along its line of symmetry and means for rotating the cams at relatively difierent speeds.

3. In an apparatus for winding spools or bobbins, a traverse actuating mechanism comprising a rotary drive shaft, a main cam operatively connected for rotation to the drive shaft, said main cam being of symmetrical shape and adapted to control the thread guide arm of the traverse mechanism, an auxiliary cam located in closely spaced parallel relation to the main cam and independently rotatable with respect thereto, means supporting the main cam for displacement along its line of symmetry, means extending between the main cam and auxiliary cam whereby relative rotation between the cams causes displacement of the main cam along its line of symmetry and means for rotating the drive shaft and auxiliary cam.

4. In an apparatus for winding spools or bobbins, a traverse actuating mechanism comprising ,a rotary drive' shaft, a main cam operatively connected for rotation to the drive shaft, said main "cam being of symmetrical shape and adapted to control the thread guide arm of the traverse mechanism, an auxiliary cam located in closely spaced parallel relation to the main cam and independently rotatable with respect thereto about an axis corresponding to the axis of said drive' shaft, means supporting the main cam fordisplacement along its line of symme'try, means extending from the main cam and yieldingly main tained in engagement with the periphery of the auxiliary cam whereby relative rotation between the cams causes displacement of the main cam along its line of symmetry and means for rotating the drive shaft and auxiliary cam at relatively different speeds.

5. In an apparatus for winding spools or bobbins, a traverse actuating mechanism comprising a rotary drive shaft, a main cam operatively connected for rotation to the drive shaft, said main cam being of symmetrical shape and' adapted to control the thread guide arm of the traverse mechanism, an auxiliary cam located in closely spaced parallel relation to the main cam and independently rotatable with respect thereto, means supporting the main cam for displacement along its line of symmetry, means extending between the main cam and auxiliary cam whereby relative rotation between the cams causes displacement o'f the main cam along its line of symmetry, means for rotating the drive shaft and speed change mechanism operatively connected to the drive shaft for rotating the auxiliary cam at a diiferent speed relative to the drive shaft. I

6. In an apparatus for winding spools or bobbins, a traverse actuating mechanism comprising a main cam of symmetrical shape and adapted to control the thread guide arm of the traverse mechanism, an auxiliary cam located adjacent the main cam and independently rotatable with respect thereto, means supporting the bins, a traverse actuating mechanism comprising a rotary drive shaft, a hub fixed to the drive shaft and having a crank arm extending radially therefrom, a main cam of symmetrical shape loosely associated with the hub, and adapted to control the thread guide of the traverse mechanism, a guide member rigidly fixed to the main cam and having an elongated slot therein disposed parallel to the line of symmetry of the main cam, a pin extending laterally from the crank arm and receivable in the slot for imparting rotation to the guide member and main cam, a bushing surrounding the drive shaft and independently rotatable with respect thereto, an auxiliary cam fixed"to said bushing and located adjacent the guide member, a roller' carried by said guide member, spring means yieldingly urging said roller into engagement with the periphery of the auxiliary cam whereby relative rotation between the'cams causes displacement of the main cam ANTONIE J ACOBUS ENGEL. 

